| 摘要 |
A direct current (dc) uninterruptible power system is disclosed. The dc-based uninterruptible power system includes a multiplexer, a battery unit, a linear regulator, a switch-transistor, a voltage comparator and micro controller. The multiplexer receives a first control signal, a first reference voltage and a second reference voltage and outputs a control voltage according to the first control signal. The switch-transistor has a body diode and the body diode has a conduction voltage. When the dc-based uninterruptible power system is non-discharge mode, the switch-transistor is switched-off and the linear regulator receives the first reference voltage, so that the subtraction of the output voltage and the power-supply voltage is smaller than the conduction voltage to cutoff the body diode. |
| 主权项 |
1. A DC-based uninterruptible power system, electrically connected to a DC power supply, the dc-based uninterruptible power system outputting a DC voltage to be served as a supply voltage in a non-discharge mode and providing the DC voltage to a load, wherein when the DC power supply interrupts electric power, the DC-based uninterruptible power system enters a discharge mode, the DC-based uninterruptible power system comprising:
a multiplexer, electrically receiving a first control signal, a first reference voltage and a second reference voltage, and outputting a control voltage according to the first control signal, wherein the control voltage is either the first reference voltage or the second reference voltage; a battery unit, electrically connected to the DC power supply via a charging circuit, the battery unit being used for outputting a discharge current in the discharge mode; a linear regulator, electrically connected to the battery unit for receiving a battery voltage and electrically connected to the multiplexer for receiving the control voltage, and selectively outputting an output voltage in normal on-state with the discharge current from the battery unit to the load in the discharge mode according to the control voltage, wherein different voltage values of the control voltage are corresponding to different voltage values of the output voltage; a switch transistor, having a gate, a drain, a source and a body diode, wherein the gate of the switch transistor electrically connected to the multiplexer so as to receive a second control signal and accordingly determining switched-on state or switched-off state, the drain of the switch transistor electrically connected to the linear regulator so as to receive the output voltage, the source of the switch transistor electrically connected to the load, and the body diode has a conduction voltage and when the DC-based uninterruptible power system is in non-discharge mode, the control voltage received by the linear regulator is the first reference voltage and the switch transistor enters switched-off state, so that a subtraction result of the output voltage and the supply voltage is smaller than the conduction voltage so as to cutoff the body diode; a voltage comparator, electrically connected to source of the switch transistor so as to receive the supply voltage, for detecting a power supply status of the DC power supply and comparing the supply voltage and a third reference voltage transmitted from an outside source so as to output a third control signal accordingly; and a microcontroller, electrically connected between the voltage comparator and the multiplexer, for receiving the third control signal and transmitting the first control signal and the second control signal to the multiplexer and gate of the switch transistor correspondingly according to the third control signal, so as to instruct the multiplexer to choose either the first reference voltage or the second reference voltage and control switched-on state or switched-off state of the switch transistor. |
